Having logged well over 1000 miles of hiking here over the last number of years, it's hard to fault a place that offers so many trails and combination of trail loops, views, wildlife, a chance to get away from the TV with the family, and of course, fresh air. We had our kids walking here when they were only 2, and they're all avid hikers now.
There's a great online trail map that can help you calculate any and every trail and trail combination too...http://www.stevenscreek.com/goodies/rancho.html
That said: parking is worse than awful, and it's only been getting worse each year too. I've seen fights (no joke) between people over a spot, and personally have had to wait over 20 minutes for a place to park at the wrong time of day (mornings/evenings and pretty much anytime on the weekends). So... carpool, or be prepared to add a mile to your walk and park at the corner of Foothill Expy in front of the church that's there.